While I am well-schooled in the ways of making pictures consisting of pixels, I am a recent, and reluctant, convert to using digital photography for my own personal work. The reasons are many, not really informed by logic, and don’t make much sense to anyone but me. Still, I have recently started venturing out into the sticks hauling one of them new-fangled digital contraptions, and I have found enjoyment and a degree of satisfaction in their use.
Now mostly when something new comes along, we all rave about how it is different from what went before, and how it allow us to accomplish all kinds of wonderful new tricks. For me, with digital landscape photography, one of these wonderful bits of newness has been the ability to bump up the ISO to make images of stars at night. I have always been very drawn to working in low light, and have made many, variably successful, star trail Images on film. I figured the digital medium would open up all sorts of new opportunities. Reflecting on a recent attempt at digital starry goodness however, has left me more aware of the similarities between the digital and film process.
In both the sample images the shooting process was nearly identical. There are only two differences worth noting: Firstly, on film, you get one go at each exposure, because all the exposures (in this case three) need to be on the same piece of film. With the digital camera bracketing exposures allows for a little more control of specific exposures, because the images are composited in photoshop and not in camera. Secondly, because I’m working on 100 ISO Fuji velvia, the film doesn’t do frozen stars: even at a wide open aperture, the exposure time is too long, and the stars start streaking.
Apart from these differences though, the shooting method was the same, consisting of three exposures to make each image. The first exposure was made well after sunset when the ambient light was dim, but soft and very even. This exposure is used to establish some general, softly lit detail all over the scene. On the digital camera the shot was bracketed to give different renditions, safe in the knowledge that the most appropriate one could be picked at a later stage. The first film exposure had to be more exact, since the three shots would all be exposed onto the same sheet of 4 x 5inch film, to make a final composite in camera. This base exposure was underexposed by about 2 stops to keep the detail very subdued. The digital base exposure was 15 sec, F11 at 200 ISO. The film base exposure was made at 1 minute @ F32 after getting a reading of 30 sec @ F32, with about a stop’s worth of reciprocity failure taking care of the second stop of underexposure.
The second exposure was made once it had gone almost completely dark. In each instance an exposure of indeterminate length was made, during which time some details in the scene were painted with light. The digital exposure was again made At F11 and 200ISO, and the total time was roughly 4 minutes. For the film image the aperture was opened to F16 to give the torch a longer reach, and the main rock and some surrounding details were painted. The exposure time was not recorded, though it was probably at least 10 minutes.
The final exposure is where the execution diverges a little more. For the film image the aperture was opened to F5.6, and the shutter left open for about 6 Hours. At F5.6 the stars aren’t really in focus, but because they streak anyway, it is not really noticeable. For the digital image, the aperture was opened all the way to F2.8, and the ISO turned up to 1600. Exposures were made at 30 sec and 1 minute, and I ended up using the 1 minute exposure. The digital stars are also a little out of focus at 2.8, and interestingly the stars on the left side of the frame are slightly streaked while the ones on the right are still. Why? Because the stars on the right are more directly south, meaning they move less in relation to the camera as the earth turns.
In both instances the camera was left untouched between exposures, to make sure the separate exposures align perfectly. For the film image the film holder remained in the camera without a darkslide, to make sure there is no chance of accidentally moving the film in the holder, or aligning the holder differently when reinserting it.
At this stage the film image was done, and only had to be taken to the lab for processing. The digital images had to be selected, processed in lightroom, sent to photoshop and composited to arrive at a final result.
To me the film image feels like more of an accomplishment than the digital one. Having only one opportunity to nail each step makes the stakes a lot higher, and its not unlikely at all that you could come away with nothing to show for your efforts. This image has worked out quite well, though I think the base exposure was too bright, leaving the sky paler than ideal and obscuring the stars a little. The process that goes into making the digital image is way more flexible, and allows many opportunities to catch and fix mistakes on the fly, and only combining the images after shooting allows far more control over the interplay between the different components. In the end this control has made it possible to tweak the image to almost exactly match my vision for the scene, but it has robbed the process of a sense of serendipity.
So, which is my favourite? Guess. Its not hard…